Pedestrians walk on a street in the Gangnam district of Seoul on Sept 14, 2023. (PHOTO / AFP)

SEOUL - The number of young South Koreans was expected to halve in 30 years amid the rapidly aging population and the record-low birthrate, the country's statistical agency said Monday.

The number of those aged 19-34 totaled 10,213,000 in 2020, taking up 20.4 percent of the country's total population, according to Statistics Korea.

The number was forecast to drop to 5,213,000 in 2050 after steadily declining from 13,849,000 in 1990 to 12,883,000 in 2000 and 10,967,000 in 2010.

The percentage of youth to the total population was forecast to tumble to 11.0 percent in 2050.

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In this file photo dated Feb 24, 2021, a group of women walk along a street in Seoul. (PHOTO / AFP)

The total fertility rate, or an average number of children a woman is expected to bear in her lifetime, hit a new low of 0.78 in 2022 amid rapid population aging.

The percentage of unmarried young people to the total youth population soared to 81.5 percent in 2020 from 75.0 percent five years earlier.

The figure has been on the fast rise from 54.5 percent in 2000 to 63.2 percent in 2005 and 68.9 percent in 2010.

The proportion of the economically active young women to the total young women had been on the increase from 42.3 percent in 2000 to 55.2 percent in 2010 and 61.1 percent in 2020.

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The percentage of the economically active young men had roughly been on the decline from 66.0 percent in 2000 to 64.7 percent in 2010 and 63.9 percent in 2020.